Cell reselection and cell handover are important functions of a mobile communication system. In order to achieve a smooth cell reselection, a User Equipment (UE) needs to measure signal quality of different cells so as to select a proper cell for camp. In order to meet the demand on mobility, after being connected with a network in a cell, the UE still needs to measure signal quality of neighboring cells to select a proper cell for a handover. During a measurement, a network side in a connected state sends a measurement control message to a UE, and the UE needs to send a measurement report according to the content in the measurement control message. Here, the content encapsulated in the measurement control message comprises: a Measurement Object (MO), measurement report configuration information (Report Configuration, RC), a Measurement ID (MID), a measurement threshold (s-Measure), measurement quality configuration and measurement interval configuration; wherein the MO may be a frequency, a group of frequencies or a group of cells on one or more frequencies; the RC is used for configuring attributes of a measurement report, for example, event-triggered reporting or periodically-triggered reporting as well as the configuration corresponding to each report type; the MID is an identifier which corresponds to a specific measurement task and associates one MO with one RC; the s-Measure is a measurement threshold value of signal quality of the cell where the UE currently camps; the measurement quality configuration is used for indicating specific measurement quality; and the measurement interval configuration is used for configuration information such as differ-frequency measurement.
It should be noted that the measurement task involved in a measurement can be explained as a measurement task constituted by an MO and RC corresponding to an MID, for example, an MO corresponding to MID 1 is frequency A and corresponding RC is that: if there exists a cell on the frequency A with signal quality greater than s-Measure, the reporting of the measurement is triggered by an event, then a measurement task is performed. An MID is used for identifying a configured measurement task so that a UE can know the number of the configured measurement tasks by calculating the number of the configured MIDs, and the attributes of the measurement task, for example, an MO (frequency A or frequency B) and a report type of a measurement (periodically-triggered reporting or event-triggered reporting), can be obtained through the MO and RC corresponding to the MID. After receiving a measurement control message, the UE stores configuration content associated with the measurement in its own variables, for example, in a variable VarMeasConfig for storing measurement-related configuration content including a configured MO list, an RC list, an MID list as well as s-Measure, a measurement quality configuration and a measurement interval, etc.
In the 3rd mobile communication Long-Term Evolution (LTE) system, a UE can perform a measurement according to the following measurement rule.
For each configured MID (namely, each MID stored in a measurement configuration variable), if a measurement interval is needed by and configured for an MO corresponding to an MID and the necessary measurement condition is met that a value of signal measurement quality of the cell where the UE camps is less than configured s-Measure or no s-Measure is configured, then the UE performs a measurement on the MO corresponding to the MID.
That is, after the necessary condition is met, if radio quality of the serving cell is good enough, i.e., the value of the signal measurement quality of the cell where the UE camps is greater than the s-Measure, the UE performs no measurement, thus reducing the measurement times of the UE; or if a special measurement interval is needed for a different-frequency MO measurement but there exists no measurement interval, the UE performs no measurement but always measures other MIDs.
Measurement reporting is classified into event-triggered reporting and periodically-triggered reporting. The reporting of a measurement is triggered by an event when the following condition is met: first, signal measurement quality of an MO corresponding to an MID is measured, and then, a measurement is triggered only when the signal measurement quality of the MO meets a event-triggered reporting condition, for example, the event-triggered reporting condition is that an event is triggered when measured radio signal quality of a neighboring cell is 3 db higher than that of the cell where the UE camps. The reporting is performed only once or many times at a given time interval. FIG. 1 is a schematic diagram illustrating the reporting of a measurement triggered by an event, as shown in FIG. 1, after receiving a measurement control message from a network side, a UE sends a measurement report many times in an event-triggered reporting manner at a reporting interval after an event is triggered. For the periodically-triggered reporting, measurement reporting is started once a report number is acquired and performed at a report interval, the difference from the situation in event-triggered reporting lying in that in this case the reporting is started without meeting the event-triggered reporting condition. FIG. 2 is a schematic diagram illustrating the reporting of a measurement triggered periodically, as shown in FIG. 2, after receiving a measurement control message from a network side, a UE sends a measurement report many times in a periodically-triggered reporting manner at a report interval. In order to save network resources, the report time of the periodically-triggered reporting can be limited by setting a maximum report time, i.e., a periodical measurement is configured by the network side for the UE, the UE creates a node measurement report VarMeasReport in its own measurement report list variable, for example, VarMeasReportList, every time the reporting of a measurement task is started, wherein the measurement report list variable, which is presented in the form of a list or an array, is only used for storing an MID and a report counting value corresponding to the MID, and each node measurement report in the measurement report list variable, i.e., VarMeasReport, takes the MID as its keyword, wherein the report counting value of the current measurement task is stored in each measurement report node, the report counting value is increased by 1 every time reporting is performed, and the reporting is ended when the report counting value is accumulated to a given report time, i.e., the accumulated report counting value is equal to the set maximum report time. The measurement report node in the measurement report list variable which takes an MID as its keyword is cleaned when the MID, the MO or RC corresponding to the MID is re-configured, and all the nodes in the measurement report list variable are cleaned when a handover or a reestablishment is performed.
The prior art is disadvantaged in that based on existing measurement rules, a UE continues measuring an MO corresponding to an MID even after the reporting of a measurement report is ended, and that the UE is always powered during the measurement, thus increasing the power consumption and other resource consumption of the UE. At present, no effective solutions have been proposed to resolve the above problem.